Tracking of floating debris from rivers around Korea

Abstract

Through a river various types of floating debris are released into the ocean. Using a Lagrangian particle tracking model, trajectories of the marine litters that are originated from five major rivers in Korea and a Chinese one are investigated. Daily ocean current data from a global model of about 1/12 degree horizontal resolution, the Global HYCOM analysis, were used in the particle model. We assumed that the amount of the litters released from each river is linearly proportional to the seasonally varying river outflow or the population over the catchment area. Particles are released from each river for one year, and then tracking is continued for another six months. Most of the particles beached coast near the river while moving with local currents. Thus the litters from the rivers located along the west coast of Korea beached on the west coast of Korea primarily, and then Chinese or Japanese coast secondarily. The ones from the river located along the southern coast of Korea are directly influenced by the Tsushima Warm Current and transported to the Japanese coast. Due to the surface circulation system in East Sea a very limited amount of litters beached on Russian coast. The trajectory of litters from the Chinses Yangtze River show strong seasonality due to surface current. In winter debris moved southwestward along the Chinese coast while in summer toward the East Sea or Kuroshio crossing the East China Sea.ted. Daily ocean current data from a global model of about 1/12 degree horizontal resolution, the Global HYCOM analysis, were used in the particle model. We assumed that the amount of the litters released from each river is linearly proportional to the seasonally varying river outflow or the population over the catchment area. Particles are released from each river for one year, and then tracking is continued for another six months. Most of the particles beached coast near the river while moving with local currents. Thus the litters from the rivers located along the west coast of Korea beached on the west coast of Korea primarily, and then Chinese or Japanese coast secondarily. The ones from the river located along the southern coast of Korea are directly influenced by the Tsushima Warm Current and transported to the Japanese coast. Due to the surface circulation system in East Sea a very limited amount of litters beached on Russian coast. The trajectory of litters from the Chinses Yangtze River show strong seasonality due to surface current. In winter debris moved southwestward along the Chinese coast while in summer toward the East Sea or Kuroshio crossing the East China Sea.